One grade point higher on a GPA was associated with a 12 percent salary increase for men and 14 percent for women. A one-point increase was also associated with doubling the likelihood of a student finishing college.

“Conventional wisdom is that academic performance in high school is important for college admission, but this is the first study to clearly demonstrate the link between high school GPA and labor market earnings many years later,” Michael French, a health economics professor and author of the study, said in a statement.

Salaries rates were measured between 24- and 34-years-old.

“High school guidance counselors and teachers can use these findings to highlight the importance of doing well in high school for both short term and longer term goals,” French said.

In addition to an overall positive correlation between a higher GPA, college graduation rates and salary, the study found that after applying controls for ability, academic performance and economic and demographic variables, the study found African-Americans performed better than white counterparts in higher education.

“One possible explanation for this finding is that African-Americans with relatively high GPAs are more motivated and determined than whites to attend college and obtain an advanced degree,” French said.